1. Field of the Invention
The present invention relates to an impeller structure, and more particularly to an impeller structure that may have a dual directional air inlet effect, and have a better air inlet and air outlet effect.
2. Description of the Related Art
A conventional blast type fan in accordance with the prior art shown in FIG. 1 comprises a casing 90 whose eddy channel is provided with a stator 91. An impeller 92 is pivoted on the stator 91 to rotate. The casing 90 is covered by a cover plate 93 which has an air inlet 94. By rotation of the impeller 92, the cool air is sucked into the air inlet 94 by the blades 95, and is drained outward from the air outlet 96. The conventional blast type fan only has a single air inlet 94 and a single air outlet 96. Thus, the conventional blast type fan can drive a smaller amount of cool air only, so that the heat dissipation effect thereof is not good enough.
Another conventional blast type fan in accordance with the prior art shown in FIG. 2 comprises a casing 80 having all air outlet 86 and having a bottom plate combined with a stator 81 and provided with an air inlet 87. Thus, when an impeller 82 of the fan is pivoted on the stator 81, rotation of the impeller 82 may suck the cool air from the air inlet 84 by the blades 85, and the air inlet 87 on the bottom plate of the casing 80 may also provide an auxiliary effect to suck part of the cool air. The air may be drained outward from the air outlet 86. The conventional blast type fan may provide an auxiliary effect to suck part of the cool air, thereby achieving the dual directional air inlet from the top and the bottom, so as to increase the heat dissipation effect. However, when the cool air is sucked from the air inlet 84 of the cover plate 83 and the air inlet 87 of the bottom plate, the cool air respectively sucked from the top and the bottom will hit each other to form a turbulent flow. Thus, the effect of heat dissipation is limited. In addition, noise will be generated during rotation.
The primary objective of the present invention is to provide an impeller structure, wherein the fan may efficiently increase the air inlet amount, so that the fan may have a better heat dissipation effect.
In accordance with the present invention, there is provided an impeller structure including a hub provided with a rotation shaft that may be pivoted to rotate. The hub has a periphery provided with an annular plate connected with the hub. A plurality of blades each have one end fixed to the annular plate and connected with a top face and a bottom face of the annular plate. The blades are extended outward from the hub in a radiating manner.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.